The present invention relates to pyrrolidinone anilines that are useful as progesterone receptor modulators.
Endometriosis is a disease characterized by the growth of endometrial tissue (called lesions) at extrauterine sites. This lesion attachment can result in pain, dysmenorrhea, dyspareunia, and infertility. It is estimated that greater than 80% of patients presenting with chronic pelvic pain are eventually diagnosed with endometriosis. The prevalence of the disease is about 7-10% of women of reproductive years with a familial association risk increase of 10-fold. Definitive diagnosis is only reached by laparoscopy, but typically there is about a ten year delay from disease onset to conclusive diagnosis. Consistent with their uterine origins, it is believed that the endometriotic lesions are hormonally dependent upon estrogen; consequently, therapies that functionally antagonize estrogen production or action, such as drugs containing progesterone receptor (PR) modulators, are efficacious in alleviating symptoms. Current therapeutic goals include reducing pain with anti-inflammatory agents and suspending the ovarian cycle using hormonal modulation drugs.
Another disease believed to be hormonally responsive to estrogen is uterine leiomyomas (fibroids), which appear as benign uterine smooth muscle tumors occurring primarily in women of reproductive age. Fibroids occur at rates of 20-25% and are the leading indication for hysterectomies. The most common symptoms are menorrhagia, pelvic pain/discomfort, bladder and bowel compression symptoms, and possibly infertility. Medical treatments for leiomyomas consist of those commonly prescribed for endometriosis, with treatments containing progesterone receptor modulators being most common due to safety, tolerability, ease of use and cost.
Most drug development has focused on modulation by full agonism or antagonism of progesterone receptors. For example, progestins are molecules that interact with progesterone receptor to activate or repress gene expression in target cells in a manner presumed to be progesterone-like. Though progestins are used in oral contraception, hormone therapy, and treatment of reproductive disorders, such as endometriosis and leiomyomas, these agents cause a number of adverse effects, including breakthrough bleeding, mood altering, acne, weight gain, and breast tenderness. Paradoxically, progesterone receptor antagonists such as mifepristone have been suggested as potential therapies, but the data are limited with few patients and no placebo-controlled randomized trials.
D. DeManno et al. (Steroids 68 (2003) 1019-1032), report that asoprisnil is a progesterone receptor modulator with mixed agonist/antagonistic activities. While the efficacy of the agent in treatment of endometriosis or fibroids is uncertain, early data from healthy female subjects indicate that the agent induces endometrial atrophy and amenorrhea, which suggests a predominantly progesterone receptor antagonist action in humans. Unfortunately, PR antagonists such as RU-486 tend to be abortifacient.
Accordingly, it would be desirable to discover a way to suppress estrogen-dependent endometriotic growth while reducing the systemic effects associated with current progesterone receptor modulating therapy.